Facultatea de Informatica va invita
vineri 29/03/2019, 12:00-16:00
12:00 – 13:15: Amf. Prof. Dr. Calin Ignat (C309)
13:15 – 16:00: C210 = C(3×70)
la un seminar stiintific aniversar.
Invitati speciali: Rodica Branzei, Gheorghe Grigoras, Florin Iacob
Prezinta: Oana Captarencu, Adrian Zalinescu si Florentin Olariu
(detalii mai jos)
Title: Modelling and Analysis of Workflows with Security Constraints
Abstract: A workflow process represents a set of coordinated tasks that take place inside an organization in order to achieve a business objective. The tasks use and produce specific data and are executed by resources in the organization. The research in the workflow area focuses on finding suitable methods to model and analyze the correctness of workflow processes when different aspects of the workflow are considered: the control-flow aspect (the tasks and their order of execution), the organizational aspect (the definition of available resources, mechanisms of allocating resources for the execution of tasks) or the data-flow aspect. If the organizational aspect of the workflow is considered, it is important to enforce security constraints, such as: authorization constraints (only authorized users can execute the tasks of the workflow), separation of duties constraints (if a user executed a specific tasks, he cannot execute a set of tasks, in order to avoid fraud or conflict of interests), binding of duties constraints (if a user executed a task he must execute a related task). We present a special class of Petri nets that permits the explicit representation of the control-flow and organizational aspects of the workflow, as well as the specification of security constraints. The organizational model uses the role-based access control policy: users are assigned to roles and the permissions to execute tasks are associated with roles. The Petri net model also allows the specification of separation of duties and binding of duties constraints. A notion of soundness is defined in order to describe the correctness of the workflow with resources and security constraints. Soundness is proven to be decidable for the proposed class of Petri nets.
Title: A Maximum Principle for Stochastic PDEs with Nonlinear Dynamical Boundary Conditions
Abstract: We study a control problem where the state equation is a nonlinear partial differential equation of the calculus of variation in a bounded domain, perturbed by noise. We allow the control to act on the boundary and set stochastic boundary conditions that depend on the time derivative of the solution on the boundary. This work provides necessary and sufficient conditions of optimality in the form of a maximum principle of Pontryagin type. We also give a result of existence of an optimal control in the case when the control acts linearly.
Title: On sequences of lattices
Abstract: We invesigate the relation between the convergence of a sequence of lattices and the set-theoretic convergence of their corresponding Voronoi cells sequence. (Work in progress.)
Va multumim pentru participare.
Faculty of Computer Science IASI